Process of dyeing cellulose acetate or products made therewith



Patented an. is, i.

rnocrss or nrnme oErLuLosn ACETATE on rnonuc'rs Mann 'rnnn r 1 1 li o Drawing.

T all whom it may 00%067'7b.

Be it known that I, RENE CLAVEL, a citizen of the Swiss Republic, of Basel, Switzerland, have invented certain new and useful 6 Improvements in the Process of Dyein Cellulose Acetate. or Products Made fherewith, of which the following is a specification.

Hitherto it'has been assumed that arti- 10 ficial silk, films and other products made with cellulose acetate are not capable of being dyed directly or by ordinary dyeing processes, owin to the water-resisting properties of the ce lulose acetate.

It has therefore been proposed to subject the cellulose-acetate products, for example artificial silk or films, to treatment with various organic or inorganic compounds before dyeing, with a view to swelling the cellulose acetate and increasing its receptivity for the dye in the subsequent dyeing process.

It has also been proposed to subject the cellulose acetate silk, films or other products to treatment with alkalies, or partial saponilication, with a view to facilitating the dyeing thereof.

It has now been found as the result of extensive research and experiment that the dyeing of cellulose acetate is not, as has hitherto 130 b n generally supposed, merely a physical phenomenon of adsorption. The remarkable discovery has been made that certain groups of dyestuffs in general-viz, hydroxyl groups,

ammo groups, iniino groups, imide 'roups, nltro groups, nitroso cups (-N=6), isonitroso roups .OH), acidylam no groups (ir-N-O .R, in which R stands for alkyl or aryl), and the azo groups.

(-N=N), hereinafter referred to as 40 active groups are active in thesense that they enable the dyestufl to enter. into chemical reaction or combination with the cellulose acetate, and that such dyestuffs, whether of the direct, acid, basic, vat or 4 other class, and whether soluble or insoluble in water, will dye cellulose acetate silk or other cellulose acetate products direct,in aqueous solution or suspension, without pretreatments such as referred to, if such active roup or groups as before mentioned are resent to a preponderatin extent in the yestufl", that is to say if t e dyestufi contains one or more of such active groups and no sulpho group, or if'the active groups are Application filed December a. 1921. Serial at. 521,008.

present in a numerically preponderant degree relatively to a su'lpho group present in the dyestufl, i, e., if there are two or more of such active groups in such dyestuff containing one sulpho group. It has been found that the presence of more than one sulpho group in the dyestuffs weakens or arrests the power of combination of the active groups with the cellulose acetate and therefore the dyeing power'of the dyestufi'. Car- The dyeing power derived from the presence of one or more active groups in the absence of sulpho-groups, or the prepondere te ingpresence of the active groups relatively to one sulpho group in various classes of dyestuffs, is illustrated for example by the following, it being understood that these are given only by way of illustration and are in no way limitative:

Monoazo-dyestufis.

Dyestufi. from aniline and betanaphthol. (Fat-soluble orun Dyes cellulose acetate very w l.

Dyestu trom paranitranlline and ea icylic acid. (Allzarln yellow- R.) Dycs well.-

Dyestuflf from betanaphthylamlne monosulphonlc acid and betanaphthol. (Silk ponceau G.) (K) Dyes well. the active groups (azo and hydroxyl) being prepomlerant over the sulpho oup.

Dyestnfl' from anil me and bctanaphthol monoaul honic acid S. (Brilliant orange G.) (M.) Dyes we 1, the active groups (am and hydroxyl) being prepcnderantover the sulpho group.

, pa e dyestuf. l J i 0 O 0 oh Pyramldolbrown B0. Dyes Well.-

Tafipiwmgl methane dyesmfis. 65

C== WP MEMO v N) I v Brilliant-alumna blue G. Dyes moderately well. Has one sulpho S l 7E5 N Fuchsia (DH). Dyes my well (N o sulpho groups.) Inwww M on fill DNn COONa OH Chrome violets (G). Dyes well, although containing carhoxyl groups. 25

'P a r fi ilndulin (water-insoluable); Dyes very well in suspension. The 90 Cl water-soluble sul honated form of this body will only dye cellulose acetate very adly I CaHoNH N(Cxm)n l Omyketones.

C Alizarin. 'Two hydroxyl groups. Dyes well.

Allzmrln ozan a. Two l1 h' ox and one nitro rou Dye bett r. g l 105 Az'me.

Anillnoblack. Dyes vea'y well. I 09mm Med thiaz'ine dyestufis;

i x H I Alizarin Bordea'uv. paste. Dyes vry well, ovying e absence 0! sin!- v i pho groups. v /9 I 11s L I Vat dyestufis of the antkmcene ems 003 v v N, 'L/ g Mesliylono blme'm. Dyes my well. 'findomiimmo XI Gnllocyanine (D E); D yes eo mallontaly. Gnllocyanines containing no sulpl ig grmpsox only on, d a well by reason or their m1- nerons vra groups and low so phonation.

Indanthrene Bordeaux B.

GO H;

Algol rosa R.

OCaHs Algol scarlet G. H

Algol yellow W G.

which contain one or more of the active 50 groups referred to, dye cellulose acetate well in aqueous suspension.

Vat dyesiufis of the indigo groups.

They dye acetate silk without vatting,'i. e. in aqueous suspension.

Natural organic dyestafis.

CH(OH) HO/ k L at 1 Logwood (haametin).

Catechu.

Dye well to the deepest shades, (e. g. as tingroups, im no groups, imlde groups, mtro groups, nitroso groups, isonitroso groups, acidylamino groups, azo groups, in t e dyestufis'enable the latter to react chemically with cellulose acetate and dye the same direct, provided that no sulpho group 15 Cochinllle.

present in the dyestufi or that only one sulpho group is present numerically preponderated by active groups; It may further be stated that this affinity and dyeing power increase with the number of active groups and decrease with the sulpho group.

In regard to basic dyes itis interesting-to observe that whereas these are generally converted into sulphonated compounds for use in dyeing other textiles, such introduction of sulpho groups-tends to render the dyeing of .celluloseacetate diflicult or im-- practicable. I have found that in proportion as the number of sulpho groups in a dyestuif isincreased the dyein power of the dyestufi' is reduced, so that or example whilst it will dye with one sulpho group present if this is numerically preponderated 35 by active groups, it may dye badly or not at all with. several sulpho groups present. According to, the invention, as regards dyeing with basic dyes containing no sulpho group, 4

one sulpho group nuor containing onl merically pre 11 erated by active groups, these are pre erably employed in conjunction with salts such for example as magneslum chloride, stannous :lllOlllClQ, zinc chlO- ride or the like which are capable of formdouble salts with the dyestuffor'in the form of such double salts. Such employment prethe dyestutl' and/the cellulose acetate. By Way 7 of example with malachite green, which can form a zinc or magnesium double chloride I it is believed that complexesare formed with the cellulose acetate molecule which may be represented for. example by the formula C H ,N,O Cl,Zn=cellulose acetate molecule,

Salts capable of flirming double salts with basic dyes mayalso according to the invention be employed with classesof dyestufis j other than "basic dyea for dyeing cellulose limits.

acetate.

The manner in which the invention can be carried out may be illustrated by the following examples, it being understood that these'are givep onl-y'bywa of illustration and'that they may be varied Within wide Ehiample 1.

' -5 kg of cellulose acetate silk are introduced into an aqueous 'de bath of a Gallocyanine dye, e.' -g.- Gal ocyanine DH and kept in inotion for, about ten minutes whilst bringing the-ten'iperature up .to or.60.

The silk is left for. about half an hour at this temperature and is then traizisferred into a bath at ordinary. room temperature, containmg acetic acid; and oil. emuls1on,-..cons1st1ng.

otolive oil and olive oil-soap Example-2. Y

ducedinto an aqueous foam bath produced accordin to-British Patent 102310, containing .inso uble 'induline in suspension. Fllhe temperature is aised to about C. while keeping silk in t e foam bath, the mechanical actionof; which brings .the suspended ilyestufi into intimate. contact" with-i the silk.

Q c'onsistingiof o ive oil andfolive oil soup. I

The suspended 'dyestufi is. taken up by the silk, which is then'transferi'ed: to a bath at 35?, containin' .Eormic acid and oil emuls on .What I claimland desire to securefby. lLfetters Patent isa- 1. A process for dyeing acetyl cellulose .in

"artificial silk, film or other fcm,comprising iiceenea the application for the direct dyeing of the acetyl cellulose in an aqueous medium, of a dyestull' having in its chemical constitution an active group content. prcpondcrant nuinerically over any sulpho group content of l the dyestult", the dyestufi' in no case containing moret an one sulpho group.

2. A process for'dyeing acetyl cellulose inartificial silk, film or .other form, comprising the application for the direct dyeing of the acetyl cellulose. in an aqueous medium, of a dyestufi' containing in'its chemical constitution a plurality of active groups and not containing. more than one sulpho group.

3. A process for dyeing acetyl celluloses in,

artificial silk, film or other-form, comprising the application for the direct dyeing of the acetyl/ cellulose in an aqueous medium, of a (lyestuli' containing in its chemical constitution an active group and no sulpho groups.

artificial silk, film or other form, comprising the application for the direct dyeing of the acetyl cellulose in an aqueous medium, of a l. A process for dyeing acetyl cellu loses indyestuft containingjn its chemical constitution a 'plurality' of active groups and no sulpho groupsr 5. .A' process artificial silk, film or other form, comprising the application tor-the direct dyeingof the acetyl cellulose in an aqueous medium, ofa

dyestu-tl of the active character referred to,

n conjunction with a salt capable of formfordyeing acetyl c'ellulosesin ing a-double saltor complex with the dyestuff and the cellulose acetate.

" 6. A process for dyeing acetyl celluloses in thread, film, or'other form, comprisin the application for the direct dyeingo" the g acetyl celluloseinan aqueous medium, of a basic dyestufi of the active character re-' ferred to, in conjunction with a salt capable of forming a. double salt or complex with the basic dyestufi' and the cellulose acetate".

7. A process. for dyeing acetyl celluloses in thread; film or other form, comprisin -;app1ic'ation, for the direct; dyeing o the j acetyl cellulose in an aqueous.medium,ot a A q J f non-sulphonated basic dyestufi'ot theactive I 5' kilos oflcelluloseacetate silk are'introcharacter referred to, in conjunction with a. salt ,capable of 'forming i a double salt or complex with the non-su-lphonated basic dyestufiancl the cellulose acetate. .1

8. A process of dyeing structures containing cellulose acetate, which comprises subthe Elli je ting,Sm r1ictures.to the action of an queousvehicle containing a, dyestufi, which includes inits structure an active group con tent preponderantnumerically' over any sulphp, group. content of the dycstufi and which a in, no case contains more-than joncsulpho group, such vehicle beingflleatd; s I testimon "vaiereof I have hereuntcs scribed my name. T'- nearer, @LAV 

